Microfabricated device with tunable spectral emission

Abstract

An apparatus may include a piezoelectric membrane, a metal layer, at least one spacer, and a reflector. The piezoelectric membrane can be configured to output light with a spectral feature. The metal layer can be disposed on a surface of the piezoelectric membrane. The at least one spacer can be disposed on the piezoelectric membrane. The reflector can be disposed on an opposite side of the at least one spacer from the piezoelectric membrane. The metal layer can be configured to actuate the piezoelectric membrane to adjust the spectral feature of the light based on a control voltage.

What is claimed is: 
     
         1 . An apparatus comprising: 
 a piezoelectric membrane configured to output light with a spectral feature;   a metal layer disposed on a surface of the piezoelectric membrane;   at least one spacer disposed on the piezoelectric membrane; and   a reflector disposed on an opposite side of the at least one spacer from the piezoelectric membrane;   
       wherein the metal layer is configured to actuate the piezoelectric membrane to adjust the spectral feature of the light based on a control voltage. 
     
     
         2 . The apparatus of  claim 1 , wherein a geometry, a thickness, and an electrical actuation of the piezoelectric membrane are determined to optimize the spectral feature of the light emitted by the piezoelectric membrane. 
     
     
         3 . The apparatus of  claim 1 , wherein: 
 the metal layer comprises multiple electrodes, and   a pattern for metal electrodes is determined to optimize the spectral feature of the light emitted by the piezoelectric membrane.   
     
     
         4 . The apparatus of  claim 1 , wherein an initial distance between the metal layer and the reflector is based on the spectral feature of the light emitted by the piezoelectric membrane. 
     
     
         5 . The apparatus of  claim 1 , wherein the piezoelectric membrane comprises at least one of aluminum scandium nitride, lithium tantalate, and lithium nitride. 
     
     
         6 . The apparatus of  claim 1 , wherein the metal layer and the reflector comprise at least one of platinum, palladium, and nickel. 
     
     
         7 . The apparatus of  claim 6 , wherein the metal layer and the reflector do not comprise gold. 
     
     
         8 . An apparatus comprising: 
 an array of thermal devices, each thermal device comprising: 
 a piezoelectric membrane configured to output light with a spectral feature; 
 a metal layer disposed on a surface of the piezoelectric membrane, wherein the metal layer is configured to actuate the piezoelectric membrane to adjust the spectral feature of the light based on a control voltage; 
 at least one spacer disposed on the piezoelectric membrane; and 
 a reflector disposed on an opposite side of the at least one spacer from the piezoelectric membrane; and 
 one or more processors configured to regulate, for each thermal device, the control voltage applied to the metal layer. 
   
     
     
         9 . The apparatus of  claim 8 , wherein, for each thermal device, a geometry, a thickness, and an electrical actuation of the piezoelectric membrane are determined to optimize the spectral feature of the light emitted by the piezoelectric membrane. 
     
     
         10 . The apparatus of  claim 8 , wherein, for each thermal device: 
 the metal layer comprises multiple electrodes, and   a pattern for metal electrodes of the metal layer is determined to optimize the spectral feature of the light emitted by the piezoelectric membrane.   
     
     
         11 . The apparatus of  claim 8 , wherein, for each thermal device, an initial distance between the metal layer and the reflector is based on the spectral feature of the light emitted by the piezoelectric membrane. 
     
     
         12 . The apparatus of  claim 8 , wherein, for each thermal device, the piezoelectric membrane comprises at least one of aluminum scandium nitride, lithium tantalate, and lithium nitride. 
     
     
         13 . The apparatus of  claim 8 , wherein, for each thermal device, the metal layer and the reflector comprise at least one of platinum, palladium, and nickel. 
     
     
         14 . The apparatus of  claim 13 , wherein, for each thermal device, the metal layer and the reflector do not comprise gold. 
     
     
         15 . A method comprising: 
 disposing a metal layer on a surface of a piezoelectric membrane configured to output a light with a spectral feature;   disposing at least one spacer extending from the piezoelectric membrane; and   disposing a reflector on an opposite side of the at least one spacer from the piezoelectric membrane,   wherein the metal layer is configured to, based on a control voltage, actuate the piezoelectric membrane to adjust the spectral feature of the light.   
     
     
         16 . The method of  claim 15 , further comprising: 
 determining a geometry, a thickness, and an electrical actuation of the piezoelectric membrane to optimize the spectral feature of the light emitted by the piezoelectric membrane.   
     
     
         17 . The method of  claim 15 , further comprising: 
 determining a pattern for metal electrodes of the metal layer to optimize the spectral feature of the light emitted by the piezoelectric membrane.   
     
     
         18 . The method of  claim 15 , wherein an initial distance between the metal layer and the reflector is based on the spectral feature of the light emitted by the piezoelectric membrane. 
     
     
         19 . The method of  claim 15 , wherein the piezoelectric membrane comprises at least one of aluminum scandium nitride, lithium tantalate, and lithium nitride. 
     
     
         20 . The method of  claim 15 , wherein the metal layer and the reflector comprise at least one of platinum, palladium, and nickel.